Machinery



No Model.)

5 Sheets-Sheet 1. E. E. JOHNSON. PUMPING MACHINERY.

No. 595,175. Patented Deo. 7, 1897. 7% c4 (No Model.) 5 Sheets-Sheet; 2.

E. E. JOHNSON.

PUMPING- MACHINERY.

No. 595,175. Patented Deo. 7, 1897.

(No Model.)

5 Sheets- Sheet 3. E. E. JOHNSON.

v PUMPING MACHINERY.

No. 595,175. Patented 1300.7, 1897.

(No Model.) 5 Sheets-Sheet 4.

E. E. JOHNSON.

PUMPING MACHINERY.

No. 595,175. Patented Deo. 7, 1897.

f -J n f ff JZ? jf one rari/hbz ZQ' a. f 0? w *w a7 dY" 5 Sheets-Sheet 5.

(No Model.)

E. E. JOHNSON.

PUMPING MACHINERY.

No` 595,175. Patented Deo, 7, 1897.

m: Noams wenns co. vnorovLxTNoM/Asnmmm, o c

lhvTTnn STATES PATENT Trice,

EDYVARD E. JOHNSON, OF CHICAGO, ILLINOIS, ASSIGNOR TO VAIIEMAN B.

IIENION AND CHARLES W'. I-IUBBELL, OF SAME PLACE.

PUIVIPING MACHINERY.

SPECIFICATION forming part of Letters Patent No. 595,17 5, dated December 7, 1897. Application filed February 29, 1896. Serial No. 581,331. {No model.)

T all whom, iz? Hefty concern:

Be it known that I, EDWARD E. JOHNSON, of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Pumping Machinery, of

which the following is a specification.

My invention relates to power-pumps of the class in which two single-acting pl u ngers operating in conjunction with a single discharge- Io passage are reciprocated by separate crank connections at an equal number of strokes per minute.

A principal object of the invention is to provide pumps of this character with an improved driving mechanism by which the movement of the two plungers is so varied from that resulting from the ordinary crank motion that a continuous and in large degree constant How will result in the common discharge-pipe, and by which the shocks and strains on the pump incident to its working under any given load will be reduced to a minimum.

The invention consists in the matters herein set forth, and particularly pointed out in the appended claims.

In a machine embodying my invention the driving mechanism for each plunger embraces a crank-shaft or equivalent rotative part having a crank-pin to which the plunger connect- 3o ing-rod is attached and a separate rotative driving part arranged eccentrically to the first part upon an axis parallel to the axis of said `first part. One of said parts is provided with a wrist-pin and the other with a groove, into which the wrist-pin projects and within which it slides as it approaches to and recedes from the center of revolution of the grooved part in its eccentric movementabout the same. In many instances the driving part will be a second shaft arranged almost end to end with the crank-shaft, but offset somewhat therefrom, so that the axes of the two shafts are parallel instead of continuous. At their adjacent ends the two shafts will be provided with crank-arms or the like, which rotate in parallel planes in close proximity to each other, one of said crank-arms being provided with the wrist-pin and the other with the coactin g groove, as described. The driving part 5o is given a uniform rotary movement from any suitable source of power and transmits a rotary movement to the driven or pump-crank part through the engagement of the wrist-pin and slotted groove. Owing tothe eccentricity of the parts, however, the rotary movement resulting in the driven part is not uniform, but is alternately faster and slower in each revolution, and the relative arrangement of the several elements is made such that the operative or discharge stroke of the connected plunger occurs during the slow half of the revolution of its crank, while its return or idle stroke occurs during the other or rapid half of the revolution. The driving connections are precisely similar for both plun gers oi' the pump, and the number of revolutions per minute is the same in each, the driving parts being ordinarilyprovided with intermeshing gears of equal diameter. The two mechanisms are,furthermore,so arranged with respect to each other that the strokes of the two plungers occur in alternation-t`- e., the return stroke of one plunger takes place during the discharge stroke of the other plunger. Inasmuch, however, as each discharge stroke occupies a considerably-longer interval than the return stroke,for the reasons hereinbefore stated, each plunger completes its return and commences its discharge stroke again before the discharge stroke of the other plunger is completed. The column of water in the common discharge-pipe therefore is never free from the actuating impulse of at least one of the plungers, and with a proper proportion and correct relative arrangement of the parts the discharge is not only continuous, but in a large degree approximates a constant flow.

A further development of the invention has for its object to reduce the acceleration and consequent shock ordinarily incident to the beginning and early part of cach working stroke of a crank-driven plunger Without reducing the capacity of the pump or the number of strokes per minute by securing a slower movement of the crank as it passes its lower dead-center and prolonging the period over which the increase of plunger speed to its maximum is distributed and by subsequently making up for the reduced amount of work performed during this period by prolonging the period of maximum dischargexo a later IOO produces, in effect, a rocking motion of the crank-shaft, by which the pump-crank falls still farther behind in the iirst portion of its upward movement, but begins to overtake the wrist-pin again in. the latter portion of its movement, and finally completes said movement at a rate of speed due to the previous entrance of the wrist-pin upon that portion of its orbit during which it effects the faster half-revolution of the crank-shaft.

An actuating mechanism constructed in accordance with myimprovements is particularly well adapted for use in that class of liftpumps in which two valved plun gers are arranged one above the other in the same cylinder. Pumps of this kind are commonly employed in bored wells of small diameter, and the cylinder proper usually constitutes one section of a straight continuous pipe, which also forms the suction and discharge pipes and may serve as the casin g of the well. When the well is of considerable depth, as is frequently the case in practice, the weight of the water within said pipe is very great and the shock incident to any sudden checking or acceleration of its iiow is correspondingly severe. The more uniform movement of the column resulting from the improvements described relieves the pump to a material eX- tent from such shocks and greatly reduces the wear and tear. It also increases the efficiency of the apparatus by decreasing lthev loss of power due to the dissipation of the` momentum of the column incident to an intermittent movement. i

The invention will be more fullyvunderstood from the following detailed description of the construction illustrated in the accompanying drawings, which show some of the forms in which the improvements may be practically embodied.

In said drawings, Figure 1 is a vertical sectional elevation of a deep-well pumping plant of the character hereinbefore referred to. Fig.

2 isa top plan view of the actuating mechanism thereof. Fig.- 3 is a transverse sectional view taken on line 3 3 of Fig. 2. Fig. 4 is an enlarged end View of a pump crank-shaft, showing the grooved crank. Fig. 5 is a side view thereof. Fig. 6 is a detailed end view of the grooved crank, showing the slide and wrist-pin within it. Fig. 7 is a diagrammatic View showingthe relative position of the parts of the pump shown in Figs. 1 and 2 at various points in the revolution. Fig. 8 is a similar view showing the relations of such parts as they would be if the grooves were in the same radial planes with the pump-cranks. Fig. S), is a graphical lay-out of the discharge and suction lines produced by mechanisms operating as shown in Figs. 7 and 8. Fig. 10 is a similar View of the discharge and suction lines of the ordinary double-plunger lift-pump. Fig. 11 is a diagrammatic view showing the relative relations of the crank and wrist pins to the grooves when the driving-shafts are arranged in a common plane with the two crank-shafts and between the latter. Fig. 12 is a similar view showing the relations of said parts in a construction in which the driving-shafts are arranged above the crankshafts. Fig. 13 shows a double-plunger liftpump with separate cylinders, and Fig. 14 a more compact arrangement of the driving parts.

In said drawings, A designates the pumpcylinder, and B B are valved plungers arranged one above the other within the cylinder. Said plungers may be of any preferred construction having valves, such as b h', which open freely to permit the free upward movement of the current, but close instantly to prevent any return or downward movement thereof. The cylinder A is, in effect, simply a lower section of a continuous vertical pipe A', but is preferably made of slightly-reduced diameter in order to permit the plungers B B to be readily withdrawn for inspection and repair. The pipe A depends from a connected cast-iron chamber A2, which rests upon a suitable foundation beneath the operating mechanism of the pump. From the chamber A2 a pipe A3 leads to any connection or point of discharge desired-as, for example, to the service pipes or reservoir of a Waterworks system.

The opera-tive mechanism of the pump is herein shown as supported by -beams G above a pit C, at the bottom of which the chamber A2 is located. Parallel crank-shafts D D are journaled upon a base-plate C2, that y rests on the I-beams C, and are provided with cranks d and d', from which connecting-rods E E extend downwardly to cross-heads F F. The latter are arranged to reciprocate vertically between guides f f that are rigidly supported within the pit in any suitable manner, the connecting-rod E being'made of greater length than the connecting-rod E and the cross-head F being located at a correspondingly lower level than the cross-head F. Said cross-head F is rigidly attached to the upper end of a tubular plunger-rod h2, which extends vertically downward through a stufling-box o; in the chamber A2 and carries the upper plunger -B at its lower end. The cross-head F'v is rigidly attached to a smaller plunger-rod h3, which passes down through the hollow plunger-rod b2 and supports the lower plunger B. The plunger-rod h3 is free to reciprocate withinthe plunger-rod b2, and a stuffing-box b4 is IOO provided at the cross-head F or at any other suitable point to prevent leakage through the hollow rod ZP around said inner rod b3.

The crank-shafts D D' are rotated by driving-shafts G G', which are journaled in the same horizontal plane with the crank-shafts, but are offset laterally therefrom, each driving-shaft being herein shown as located on the side of its crank-shaft toward the other crank-shaft, and the eccentricity of the driving-shaft to its crank-shaft being the same in each case. Said driving-shafts are designed to rotate at the same rate of speed and are in this instance provided with intermeshing gears G2 G3 of equal diameter.

The driving power is applied in any suitable manner-as, for example, by a large gear G, which is keyed to the end of the shaft G and internieshes with a driving-pinion G5 on a counter-shaft G-and the direction of rotation is such that the shaft and gears move upwardly upon their inner or adjacent sides. The ends of the driving-shafts nearest the crank-shafts carry crank-arms g g, from the faces of which wrist-pins g2 g3 project in the direction of the crank-shafts, and the latter are provided at their adjacent ends with crank-arms (Z2 (Z3, which are grooved on their outer faces at d* to receive the wrist-pins g2 To reduce the friction and wear, the wristpins, as herein shown, do not come directly into contact with the walls of the grooves d", but are journaled within slides g4 g5, which tit and are adapted to reciprocate within said grooves; but the resulting movement is obviously the same as though such slides were omitted. Each wrist-pin travels in an eccentric circle about the adjacent crank-shaft and exerts a continuous pressure in one rotative direction upon the groovcd crank thereof. The angular velocity of the rotary movement thus produced in each crank, however, varies throughout each revolution and at any given instant will be faster or slower than the angular velocity of the drivin g-shaft in the proportion that the distance from the wrist-pin to the axis of the driving-shaft at that instant is greater or less than its distance from the axis of the crank-shaft. The relative angular location of the pump-crank and grooved crank on each shaft is nearly the same, and the upward-and-downward movement of the pump-crank consequently occurs in substantial coincidence with the corresponding movements of the wrist-pin. During its downward movement the latter is nearer the crankshaft and, in accordance with the rule above stated, imparts an increased angular velocity to the latter and a consequent rapid downward movement of the pum p-crank. During its upward movement the wrist-pin is farther from the crank-shaft and imparts to it a decreased angular velocity, thereby causing' a slow upward movement of the pump-cran k. The lifting or working stroke of each plunger is therefore correspondingly slower than its downward stroke, and as the intermeshing gears G2 and G3 on the driving-shafts are adjusted to maintain the two pump-cranks in relative opposite portions of their respective paths of revolution the quick downward stroke of one plunger occurs during the long upward stroke of the other plunger, and the upward strokes of both plun gers consequently overlap at both ends. The working stroke of each plunger, furthermore, occurs at the time that its operating wrist-pin is engaging the outer end of the groove d4 and is consequently working with its longest leverage and with the least necessary strain on the driving parts.

The operation of the plungers upon the water column is substantially as follows: At least one of the plungers is always moving upward, driving before it the column of water in the discharge-pipe and drawing after it the column in the suction-pipe or lower part of the cylinder. Vhen the lower plunger is moving downward or is rising at a less rate of speed than the upper plunger, its valve b opens and permits the water from the well to follow up the upper plunger. As the latter approaches the upper limit of its movement the lower plunger begins to rise, and as soon as its increasing speed equals or surpasses the decreasing speed of the upper plunger said valve b/ closes. The load is now transferred to the lower plunger and the water is lifted thereby through the valve l) in the upper plunger. The latter then completes its upward movement and rapidly descends through the rising discharge-column in time to begin its upward stroke again before the upward stroke of the lower plunger is completed. As its increasing speed in turn equals and surpasses the now decreasing speed of the lower plunger the valve l) closes and the load is shifted again to the upper plunger. At the same time the valve l1' again opens and the lower plunger completes its stroke and descends freely'through the ascending suctioncolumn. The resultant effect of the operation of the two plungers, therefore, is to compel a continuous discharge in which the variation from maximum to minimum will frequently not exceed about thirty per cent. While the relative angular location of the grooved cranks and pump cranks on the shafts is nearly the saine, as hereinbefore stated, the grooves d4 do not in the approved construction shown stand exactly in the radial planes of the pump-cranks, but for the purpose of still further improving the very effective action thus above described are in this instance arran ged to intersect the latter at the limit of innermost movement of the wrist-pins and extend outwardly and forwardly from such points of intersection at a considerable angle, in this instance thirty degrecs, with said planes-i. e., the grooves d" are so located with reference to the pumpcranks that when either wrist-pin reaches its outermost position and stands in the same horizontal plane with its driving and crank shafts the pump crank-pin op will also stand IOO IIO

in that plane, and the groove d4 will extend outwardly from the wrist-pin in front of the pump-crank and at the above-mentioned angle therewith. (See Fig. 11.) XVith this construction the pump-cranks lag behind the wrist-pins in the lower half of each revolution and overtake them again in the upper half-revolution. The crank-shafts are consequently rotating at a less angular velocity when the pump-'cranks begin their upward or working movement than would otherwise be the case, and the initial upward movement of the plungers is correspondingly slower. rlhe lag of the crank, moreover, continues to increase almost to the middle of the upward movement and reduces the acceleration naturally incident to the iirst quarter of a crank motion, thereby correspondingly reducing the extra load thrown on the plunger at each revolution by reason of such acceleration. On the other hand, the return forward movement of the pump-crank relatively to the wrist-pin which begins at the middle of the upward stroke acts in opposition to the decrease in plunger speed incident to the second quarter of a crank motion and prolongs the effectiveness of the stroke to a later point in the revolution. In other words, the effect of the abovedescribed peculiar relative location of the pump-cranks and grooves is to more equally distribute the work throughout the entire stroke and reduce the wear and tear accordingly. IVith the ordinary crank movement the extra load thrown on the plunger in the iirst half of each working stroke by reason of the acceleration imparted to the column of water during this period constitutes a very material portion of the total maximum load which the working parts must be designed to carry, and the suddenness with which the load is applied produces a shock which adds very greatly to the tendency toward breaking.- 1 Any reduction in the load due to acceleration therefore results directly in decreasing the required strength of the parts and reducing the frequency of breakdowns. A somewhat similar modification of the acceleration effects would. be accomplished by making the grooves d4 radial and arranging the pump-cranks at a suitable angle behind them; but the particular construction shown is deemed to be the most effective yet devised for the purpose. It will, moreover, be understood that in any case the relative angular arrangement of the grooved cranks and pumpcranks is directly dependent upon the relative location of the driving and crank shafts,

- so that if the driving-shafts were placed in any other position with relation to their crankshafts than that shown-viz., on the inner1 sides of and in the same horizontal plane with said crank-shafts-a corresponding change would have to be made in the position of the pump -cranks with relation to the grooved cranks, since otherwise the upward or working movement of the pump-cranks would not occur during the period of minimum angular velocity of the crank-shafts. For example, in Fig. 12 I have indicated a construction in which the drivingshafts are arranged directly above the crank-shafts instead of on a level therewith and in which the pump-cranks are accordingly located about ninety degrees behind the position before described, and an indefinite number of other similar chan ges of arrangement might easily be suggested. In both Figs. ll and l2, ce designates the crankshaft centers, de the driving-shaft centers, cp the crank-pins, and wp the wrist-pins.

The relative positions of the two plungers, and of the cranks and wrist pins, at various parts of the stroke are diagrammatically shown in Fig. 7. In said figure, I-I I-I designate the centers of the crank-shafts, and II the centers of the driving-shafts. The larger circles h h', struck from the centers II II, indicate the paths of the pump crank pins, while the smaller circles t t', struck from the centers I I', indicate the paths of movement of the wrist-pins. The vertical lines J J indicate approximately the movement of the cross-heads, and consequently of the plungers, and the lines J3 J2 show therelative positions of the connecting-rods at the times the right-hand plunger reaches the upper limit of its stroke, no account being made in this diagram of the difference in length of the connectingrods. The points numbered l on each of the circles t' c" are those occupied by the wrist pins at the time the right hand plunger is at the uppermost point of its stroke, the left-hand plunger at this point being on the upward move in a position about onesixth of the entire length of its stroke from the bottom thereof. The succeeding correspondingly-numbered points 2 3 4t, the., designate equal divisions of the circles 'L' t', which divisions represent the distances traveled by the wrist pins in equal periods of time throughout the entire revolution. Thelines drawn through the numbered points and which project outwardly and forwardly therefrom in the direction of rotation of the shafts, as indicated by the arrows, represent the center lines of the grooves which receive the wrist-pins, and the points numbered 1C 2C 3, te., on the larger circles h h indicate the points occupied by the crank-pins at the time the wrist-pins occupy the points 1.2 3, &c., respectively. It will be observed that the distances between the points lC 2C 3", &c., on the outer portions of the larger circles 7L h' are much greater than the distances between the points l 2 3, &c., on the smaller circles t t" and are still greater than the distances between the similar points on the inner portions of the larger circles, and since these distances represent the travel of the crank and wrist pins during equal intervals of time in different portions of their revolution it is evident that the cranks move more and more rapidly as they approach their outermost horizontal position and less and less rapidly as they approach their innermost horizontal position,

TOO

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as hereinbefore more particularly set forth. rihe points numbered l 2 3, rbc., on the vertical lines J J designate the various positions occupied by the plungers at the time their crankpins are in the positions designated 1c 2 3G, dsc., respectively, and the points numbered the same on the two lines designate the positions of the two plungers at the same moment in various parts of their stroke. The numbers along the inner sides of the lines J J mark the progressive movements of the plungers on their upward strokes and will be observed to be spa-ced closer together than the numbers on the outer sides of the lines `which mark the progressive downward movements of the plungers, and the more rapid descent of the plungers is thus indicated. It will also be observed that the inner numbers are spaced closer together at the lower ends of the lines, thus indicating the relatively slow beginning and rapid termination of each upward stroke. By a comparison of t-he two sides of the diagram and of the correspondingly-numbered points thereon the relative position of the several parts at any given moment may readily be determined.

In Fig. S I have shown a similar diagram which differs from that shown in Fig. 7 only in representing the center lines of the grooves as located in the same radial planes with the pump crank-pins. The principal practical diiference between such a construction and that previously described lies in its failure to accomplish the desired reduction in the initial acceleration of the column with the advantages incident thereto.

In Fig. 9 I have shown a graphical representation in which the curved lines K and K represent the velocity-lines of the two plun gers in the construction shown in Figs. l and 2. Horizontal distances in this diagram represent piston movement and vertical distances velocity. Those portions of these lines above the horizontal line L, or the line of no velocity, correspond with the upward or working movement of the stroke, while those portions below the line L correspond with the downward or return stroke, the direction of movement being understood to be from right to left, as indicated by the arrows. It will be observed that the portions of the lines K K above the base line overlap considerably, thus indicating the overlapping of the working strokes of the two plungers, as hereinbefore described, and their long iiat curves show the prolonged slow action of the working stroke when compared with the short rapid action of the return stroke, as indicated by the sharp curves below the baseline. The lines M and M on the same figure are such as would be produced under the same circumstances by a mechanism of the kind shown in Fig. 8, or one in which the grooves are arranged in the saine planes with the pump-cranks- The flatter curve of the lines K K at the beginning of the upward stroke, as well as the fuller curvature of said lines toward the termination of the stroke, indicates the more gradual acceleration and better distribution of the work, due to the peculiar angular relations of the grooves and crank-shafts. The points of intersection 7tof the lines K K and the corresponding points of intersection in of the lines M M indicate the points at which the load of the ascending column is transferred from one to the other and mark the minimum discharge, and it will be observed that the distance of these points above the base-line L is nearly three-fourths of the distance from said line to the highest point of the curves, thus indicating a minimum discharge equal to nearly three-fourths of the maximum discharge. In an ordinary double-plunger lift-pump, on the other hand, the velocity-lines of the two plungers and oi' the discharge may be represented by a succession of curves N N", as shown in Fig. 10, which intersect on the base-line or line of no velocity and indicate a total cessation of flow at two points in each revolution.

In the construction illustrated in Fig. 13 my improvements are shown as applied to a lift-pump having two valved plungers O OQ arranged in separate cylinders P I, which connect with a common discharge-pipe P2. Lift-valves p p are in this case provided at the lower ends of the cylinders, and the suction-pipes P3 P3 may be separate or communicating. The flow in the discharge-pipe in this construction will be substantially the same as in the construction first shown.

Fig. la is a plan view similar to Fig. 2, but showing a more compact design of driving mechanism. In this construction the intermeshing gears Gr2 G3 rotate on stud-shafts (76 in close proximity to the grooved cranks d2 (Z3, and the wrist-pins g2 g3 project from the faces of said gears into the grooves d4.

Vhile the improvements set forth are particularly applicable to double-plunger pumps and especially to lift-pumps of the type more particularly illustrated, it will be understood that in some of its features the invention will also be advantageous as applied to singleplunger lift-pumps, especially in so far as it achieves a reduction in the acceleration and a better distribution of the load throughout the working stroke. It will also be under stood that while wrist-pins and grooves have been found to be the most desirable means yet known of communicating motion from the driving-shafts to the crank-shafts, yet nevertheless any other form of connection resulting approximately in the movement set forth maybe used and is com prehended within the broad spirit of my invention.

I claim as my inventionl. An actuating mechanism for doubleplunger pumps, comprising rotative crank elements connected with the plungers, separate rotative driving parts, cach arranged eccentric to the crank element driven thereby, and rotating sliding means applying the driving power between each driving part and its IOO IIO

crank element in a circular orbit concentric with the aXis of the one and eccentric to the axis of the other.

2. An actuating mechanism for doubleplunger pumps, comprising rotative c rank elements connected with the plungers, v'separate rotative driving parts each arranged eccentric to the crank element driven thereby, and driving` connections between each driving part and its crank element consisting of a wristepin on the one and a groove in the other into which the wrist-pin projects.

3. An actuating mechanism for doubleplunger pumps, comprising rotative crank elements connected with the plungers, separate rotative driving parts, each arranged eccentric to the crank element driven thereby, and provided with intermeshing gears ot equal diameter, and driving connections between each drivin gpart and its crank element whereby the latter moves alternately slower and faster in each revolution, the parts being adjusted to effect the idle or return movement of one plunger during the workin g stroke of the other plunger.

4. A pump provided with two sin gleacting plungers, rotative crank elements connected with the plungers, separate rotative driving parts, each arranged eccentric to the crank element driven thereby, gearing for rotating said driving parts at equal speeds, and driving connections between each driving 4part and its crank element consisting of a Wristpin on the one and agroove in the other into which the wrist-pin projects.

5. A pump provided with two single-acting plungers, rotative crank elements connected with the plungers, separate driving-shafts each arranged eccentric to the crank element driven thereby and provided with intermeshing'gears of equal diameter, and driving connections between each driving-shaft and its crank element consisting of a wrist-pin on the one and a groove in the other into which the wristpin projects.

6. An actuating mechanism for doubleplunger pumps, comprising rotative crankshafts connected with the plungers, rotative driving parts each arranged eccentric to the crank-shaft driven thereby, a grooved crank on each crank-shaft adjacent to its driving part and wrist-pins on the driving parts engaging the grooves, substantially as described.

7. An actuating mechanism for doubleplunger pumps, comprising rotative crankshafts connected with the plungers, intergeared rotative driving-shafts each arranged eccentric to the crank-shaft driven thereby, grooved cranks on the crank-shafts, and a wrist-'pin on each driving-shaft engaging the grooved crank of the crank shaft driven thereby.

8. An actuating mechanism for doubleplunger pumps, comprisi-n g rotative crank elements connected with the plungers, separate rotative driving parts each arranged eccentric to the crank element driven thereby and upon an axis located in the same plane with and between the axes of the crank elements, and driving connections between each driving part and its crank element consisting of a wrist-pin on the one and a groove in the other engaged by said pin.

9. An actuating mechanism for doubleplunger pumps,comprising rotative crank elements connected with the plungers, separate rotative driving parts each arranged eccentric to the crank element driven thereby, and driving connections between each driving part and its crank element consisting of a wrist-pin on the one and a groove on the other into which the wrist-pin projects, the relative angular arrangement of the parts being such as to retard the initial working movement of the plunger.

10. The combination with a pump-plunger of a crank element connected therewith, a rotative driving part arranged eccentrically to said crank element, and driving connections between the crank element and driving parts, consisting of a groove on the one and a wristpin on the other engaging said groove, said groove being arranged angularly in advance of the crank-pin and on a line intersecting the radial plane of the crankl between the crank-pin and its center of rotation, substantially as described.

11. The combination with a pump-plunger of a crank element connected therewith, a rotative driving part arranged eccentrically to the crank element and driving connections between the crank element and driving part, consisting of a groove on the one and a wristpin on the other which engages said groove, said goove being arranged angularly in advance of the crank-pin on a line intersecting the radial plane of the crank approximately at the point occupied by the wrist-pin at the innermost end of its travel within the groove, substantially as described.

l2. An actuating mechanism for doubleplunger pumps, comprising rotative crank elements 'connected with the plungers, rotative driving parts each arranged eccentric to the crank element driven thereby, and driving connections between each driving part and its crank element consisting of a wrist-pin on the one and a groove on the other engaged by said wrist-pin, each groove being arranged angularly in advance of the connected crank element, substantially as described.

13. An actuating mechanism for doubleplunger pumps, comprising rotative crank elements connected with the plungers, rotative driving parts arranged eccentrically to the crank elements and driving connections between the crank elements and driving parts, consisting of wrist-pins on the one and grooves on the other into which the wrist-pins project, said grooves being arranged angularly in ad- Sok IOO

IIO

vance of the crank-pins on lines which intersect the radial planes of the cranks between the crankpins and their center of rotation.

ll. The combination with two valved plungers arranged within a single cylinder, of rotative crank elements connected with the plungers, separate rotative driving parts, each arranged eccentric to the crank element driven thereby, and rotating sliding means applying the driving power between each driving part and its crank element in a eircular orbit concentric with the axis of the one and eccentric to the axis of the other.

l5. The combination with two valved plnngers arranged within a single cylinder, of rotative crank elements connected with the plungers, separate rotative driving parts each arranged eccentric to the crank element driven thereby, and driving connections between each driving part and its crank element consisting of a wrist-pin on the one and a groove in the other into which the wrist-pin projects.

1G. The combination with two valved plungers arranged within a single cylinder, of rotative crank elements connected with the plungers, separate rotative driving parts, each arranged eccentric to the crank element driven thereby, and provided with in termeshing gears of equal diameter, and driving connections between each driving part and its crank element whereby the latter moves alternately slower and fasterin each revolution, the adjustment being such as to effect the idle or return movement of one plunger during the working stroke of the other plunger.

17. The combination with two valved plungers arranged within a single cylinder, of ro tative crankshafts connected with said plungers, secondary grooved cranks on said crankshafts, separate rotative driving parts each arranged eccentric to one of the crank-shafts, and a wrist-pin on each driving part engaging the grooved crank of the adjacent shaft.

1S. The combination with two valved plungers arranged within a single cylinder, of rotative crank-shafts connected with said plungcrs, separate intergeared driving parts each arranged eccentric to the crank-shaft driven thereby, and a coacting groove and wrist-pin operatively connecting each driving part and crankshaft.

19. The combination with two valved plungers arranged within a single cylinder, of crank-shafts connected with said plungers, secondary grooved cranks on said crankshafts, separate driving parts each arranged eccentric to the crankshafts npon axes located between and in the same plane with the crank-shafts, and a wrist-pin on each driving part engaging the adjacent grooved crank.

20. The combination with two valved plungers arranged within a single cylinder, of rotative crank elements connected with the plungers, separate driving parts, each arranged eccentric to the crank element driven thereby, and driving connections between each crank element and its driving part, comprising a wrist-pin on the one and a groove in the other into which the wrist-pin projects, the groove being arranged angnlarly in advance of the connected crank element.

2l. The combination with two valved plu ngers arranged within a single cylinder, of rotative crank elements connected with said plungers, rotative driving elements arranged eccentrically to said crank elements, driving connections between the crank elements and driving parts comprising Wrist-pins on the one engaging grooves on the other, said grooves being arranged angularly in advance of the crank-pins upon lines intersecting the radial planes of the cranks between the crank-pins and their center of rotation.

22. An actuating mechanism for doubleplunger pumps, comprising rotative crank elements connected with the plungers, separate rotative driving parts, each arranged eccentric to the crank element driven thereby, and driving connections between each driving part and its crank element, consisting of a wrist-pin on the one and a non-radial groove in the other into which the wrist-pin projects.

EDVARD E. JOHNSON.

Witnesses:

HENRY W. CARTER, E. P. JOHNSON. 

